glossary

If you run across a term you have never heard before, chances are good you will find the definition in this glossary. Note: many words/phrases have more than one meaning. The meanings offered in this glossary pertain to yard care.

Acid soil, sour soil: soil with a pH measure below 7. Most soils in the eastern third of the United States and Canada and along the West Coast are naturally acidic.

Aerate, aeration: introduction of air to compacted soil by mechanically (manual or power) removing plugs of topsoil. Aeration helps oxygen, water, fertilizer, and organic matter to reach roots. Also called core cultivation or aerifying.

Agricultural waste: produced by an agricultural establishment like a commercial farm.

Agronomy, agronomist: the science of soil management, land cultivation, and crop production; the person who studies agronomy.

Air filter: prevents abrasive particulate matter from entering the engine’s cylinders, where it would cause mechanical wear and oil contamination.

Alkaline soil, sweet soil: soil with a pH measure above 7. Many central and western states have alkaline soils.

Allelopathic: an organism producing one or more bio-chemicals that influence the growth, survival, and reproduction of other organisms.

Amendments: organic or mineral materials, such as peat moss, compost, or perlite, used to improve the soil.

Annual: a plant that germinates, grows, flowers, produces seeds, and dies in the course of a single growing season. You can also use annual grasses as nurse crops to protect slower-growing seed, or to overseed warm-season grasses during their dormancy.

Anti-scalping wheels: small wheels that raise the deck to prevent the blades from contacting the ground.

Automated home sprinkler system: a method for watering lawn and plantings via underground pipes and sprinklers. A controller, when set to run, directs water to one station (valve) at a time for a specified amount of time. Afterward, it closes the valve and opens the next valve. Each station sends water to one zone, which typically consists of a group of sprinklers.

Automatic valves: electrically operated valves that turn water on and off at signals from the controller; typically buried in valve boxes, several valves to a box.

Bagging: process of collecting grass clippings. only bag when the clippings are long and wet, otherwise leave short clippings on the lawn.

Bale, bales: a large bundle or package of hay or a raw material such as cotton, tightly bound with string or wire to keep it in shape during transportation or storage.

Beneficial insects, beneficials: any of a number of species of insects that perform valued services like pollination and pest control.

Blade, blades (grass): grass blades grow at the base of the blade and not from elongated stem tips. This low growth point evolved in response to grazing animals and allows grasses to be grazed or mown regularly without severe damage to the plant. The leaf blades of many grasses are hardened with silica phytoliths, which helps discourage grazing animals; some are sharp enough to cut human skin.

Blade, blades (mower): using sharp mower blades will help produce a crisp, quality of cut and contribute to the ongoing vitality of your lawn – every time you mow.

Blade-brake clutch: When you let go of the bail on a mower, the blade safely stops but the engine continues to run. This allows you to empty the grass bag or pick up an obstacle that’s in the way without having to restart the mower.

Blend, blends: two or more cultivars of the same species.

Blowers, blower/vacuums: Gas or electric models blow leaves into piles for easier collection. Blowers are available in either hand-held, wheeled, or backpack styles, with the last two types easier for big jobs. Even if you like raking leaves on the lawn, you will appreciate a blower’s help in moving leaves out from under shrubs. Many units convert to vacuums and are quite useful for cleaning up and mulching small quantities of leaves. Electric blowers are quieter and have no emissions.

Bow saws: use for branches larger than 3-inches in diameter.

Broadcast seeding: scattering of seeds over the soil surface.

Brown-out: dormant grass; can be caused by lack of water, disease, insects, or something external applied to the grass.

Bulb planter: digs a hole and pushes the bulb into it.

Bunchgrass: the general name for perennial grass species that tend to grow in discrete tufts or clumps (i.e., bunches) rather than in sod-like carpets. Bunchgrasses tend to have deep roots and can get moisture from the soil where shallow-rooted sod-like grasses would dry out.

Burlap: coarse cloth woven from jute, hemp, or a similar rough thread.

Burnout: when grass turns yellow instead of green, you could be over fertilizing or be dealing with dog urine.

Calcium carbonate: a common substance found in rock in all parts of the world; it is the active ingredient in agricultural lime, and is usually the principal cause of hard water.

Calcitic limestone: does not contain magnesium, making it more appropriate if your soil is already high in magnesium.

Carbohydrate stores: stored in seed, crown, stem base, root, or rhizome tissues of plants, carbohydrates are the source for carbon and energy utilized in the formation of the first new leaves.

Carbon: a nonmetallic element that exists in two main forms, diamond and graphite, and has the ability to form large numbers of organic compounds.

Caster-style wheels: an un-driven, single, double, or compound wheel that is designed to be mounted to the bottom of a larger object (to enable that object to be easily moved.

Catalytic converters: a device used to reduce the toxic emissions from an internal combustion engine.

Celsius: using or measured on an international metric temperature scale on which water freezes at 0° and boils at 100° under normal atmospheric conditions. The term “Celsius” is usually preferred to “centigrade,” especially in technical contexts.

Chain saws: an electric saw is great for cutting mall tree limbs and trunks in an average-size yard. If you can keep all cutting within 100 feet of an outdoor electrical outlet, it will handle most chores, even cutting firewood. Electric saws emit no exhaust fumes, are low maintenance, low cost, quiet, and always ready to go. For bigger jobs, you will probably need a heavier gas-powered model.

Choke: a device that controls the ratio of air to fuel in the mixture supplied to an internal-combustion engine.

Clay: a type of fine soil or rock consisting mainly of hydrated aluminum silicates that occurs naturally in soil and sedimentary rock.

Climate: encompasses the statistics of temperature, humidity, atmospheric pressure, wind, rainfall, atmospheric particle count and other meteorological elements in a given region over long periods of time.

Clippings: the part of grass blades that have been cut off and either fall to the ground or are bagged.

Clover (or trefoil): a genus in the leguminous pea family Fabaceae. Legumes are ecologically important because they fix nitrogen into the soil.

Clutch: a device that enables two rotating shafts to be connected and disconnected smoothly, especially one in a motor vehicle that transmits power from the engine to the transmission.

Compaction, soil: compaction occurs when a force exerted on soil exceeds its bearing strength. As force increases, soil aggregates re-arrange or are destroyed, resulting in a structure-less soil condition. Because the soil bulk density increases drainage and aeration decreases and the soil can take years to recover.

Compost: humus made by decomposing vegetative matter in a compost bin or pile.

Control bail: a bar held against the handle of all gasoline walk-behind mowers for the blade to turn. This is a federal safety requirement to ensure the blade will stop if the user leaves the operator position.

Cool-season grasses: grasses that thrive in northern areas, including Canada, and in high elevations in the South.

Core samples: a piece of soil carved or cut, from the ground using a piece of equipment that works like an apple-corer, to see the underlying layers of soil.

Crabgrass: a coarse grass that grows in warm regions, has creeping stems that root freely, and is considered a weed in lawns and gardens. Genus: Digitaria

Crown: the part of a plant where the roots and stem meet, usually at soil level.

Culm, culms: a grass stem.

Cultivar: a cultivated variety of a plant often bred for a desirable trait, such as pest- or disease-resistance. The word “cultivar” comes from variations that came about in cultivation by deliberate breeding.

Deck: the deck is housing on a mower that covers the blade. It can be designed to discharge (a standard or broadcast deck), mulch (a mulching deck), or direct clippings to a collector (a bag or hard-shell compartment) from either the side or rear.

Deck lift or height-of-cut: a system that allows you to change cutting heights. Most are spring assisted and are operated by hand or foot.

Decomposition: to break down organic matter from a complex to a simpler form, mainly through the action of fungi and bacteria, or be broken down in this way.

Depression: a hole or a soft, bowl-shaped or dipped spot in the yard.

Dethatch: to remove thatch from turf.

Dew: moisture from the air that has condensed as tiny drops on outdoor objects and surfaces that have cooled, especially during the night.

Diatoms: a major group of algae, and one of the most common types of phytoplankton. Most diatoms are unicellular, although they can exist as colonies in the shape of filaments or ribbons (e.g. Fragillaria), fans (e.g. Meridion), zigzags (e.g. Tabellaria), or stellate colonies (e.g. Asterionella). Diatoms are producers within the food chain.

Diatomaceous earth: composed of fossilized remains of single-celled plants called diatoms, a dust is formed by quarrying and processing these ancient deposits and used in pest control.

Dielectric grease: a grease not able to conduct direct electric current, and therefore useful as an insulator.

Die-off: to die gradually one by one, until none is left.

Discharge chute: a channel for ejecting grass from a lawn mower.

Dolomitic limestone: contains magnesium, another important nutrient, as well as calcium carbonate. Use if your soil is deficient in magnesium, however do not use if your soil is already high in magnesium as this will cause problems.

Dormant: an inactive state, when growth and development slow or cease, in order to survive adverse environmental conditions.

Drain field: used to remove contaminants and impurities from the liquid that emerges from the septic tank. Another term for this is a leach field or leach drain.

Drainage: the movement of water through the soil. With good drainage, water disappears from a planting hole in less than a few hours. If water remains standing overnight, drainage is poor.

Drip irrigation: a low-pressure system for irrigating gardens, shrubs, and lawns. Emitters or sprayers release water slowly over longer periods, and applies as close to plant roots as possible. Typically used on the surface or just under the mulch of a garden bed, you can use drip irrigation underground to irrigate lawns.

Drop spreader: distributes seed, fertilizer, and other amendments, such as lime, in swaths the width of the spreader. Settings allow you to control the amount distributed.

Drought: an extended period of months or years when a region notes a deficiency in its water supply.

Dry well: an underground structure that disposes of unwanted water, most commonly storm water runoff, by dissipating it into the ground, where it merges with the local groundwater.

Earthmover: includes power shovels, bulldozers, backhoes, excavators, and more.

Edging: a shallow trench or physical barrier of metal, wood, brick, or synthetic material used to define the border between lawn turf and another area, such as paving or a flower bed.

Elemental sulfur: plants cannot absorb elemental sulfur through the root system. However, when it is added to the soil it is converted (oxidized) to a form the plant can use.

Endophytes: fungi that live in some grasses (called endophytic), making them harmful or deadly to a variety of aboveground grass-eating insects.

Endospores: a dormant, tough, and temporarily non-reproductive structure produced by certain bacteria from the Firmicute phylum.

Erosion control: the practice of preventing or controlling wind or water erosion in agriculture, land development and construction. Effective erosion controls are important to prevent water pollution and soil loss.

Evaporate, evaporation: to change a liquid into a vapor, usually by heating to below its boiling point; increases moisture in the air.

Exposure: the intensity, duration, and variation in sun, wind, and temperature that characterize any particular lawn or planting site.

Exhaust emissions standards: federally-mandated levels to help protect the environment.

Fabricated deck: deck made by welding together separate pieces of formed, heavier gauge steel for more durability.

Fahrenheit: using or measured on a temperature scale on which water freezes at 32° and boils at 212° under normal atmospheric conditions. In scientific and technical contexts, temperatures are now usually measured in degrees Celsius instead of Fahrenheit.

Fertilize: the process of feeding the lawn nutrients for growth or recovery.

Fertilizer: a substance containing nutrients.

Fertilizer ratios: tell consumers how many pounds of nutrients are contained in 100 pounds and indicate the relative amounts of nitrogen (N), phosphorus (P), and Potassium (K).

Fibrous: consisting of or resembling fibers.

Filler: frequently made from organic materials such as finely ground corncobs, help ensure even distribution of the product.

Flaming: done with a gas torch that emits a narrow flame, it heats the plant’s sap until its cell walls burst.

Foliage: the leaves of a plant or tree.

Four-cycle engine: unlike a two-cycle engine, a four-cycle does not require the mixing of oil in the gasoline. Most engine mowers today are four-cycle.

Frost heave, frost heaving: a disturbance or uplift of soil, pavement, or plants caused by moisture in the soil freezing and expanding.

Fuel stabilizer: used to extend the life of the fuel that is not or cannot be stored properly. Commonly used for small engines such as lawnmower and tractor engines to promote quicker and more reliable starting.

Full shade: a site that receives no direct sun during the growing season.

Full sun: a site that receives at least eight hours of direct sun each day during the growing season.

Fungi: large group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms, classified as a kingdom, and separate from plants, animals, and bacteria.

Fungicide: the traditional way to fight lawn disease, it kills microorganisms and fungi.

Furrow, furrows: a narrow trench in soil made by a plow or other implement.

Garden debris: organic items you remove from the garden and lawn. Consider starting a compost pile rather than disposing in the trash.

Garden rake: the steel-headed type is useful for preparing small areas of soil for the planting of seed, plugs, or sprigs.

Gauge: to determine the amount, quantity, size, or extent of something.

Gauge of steel: the lower the gauge number, the thicker the material.

Genus: indicates a group of species that have similar structural parts.

Germinate, germinating, germination: to begin to grow, or sprout, from a seed.

Glyphosate: a herbicide that is taken into the system of a plant, affecting its growth. Use: control of perennial grasses and many weeds, especially in arable fields.

Grade: the degree and direction of slope on an area of ground.

Grape (grubbing) hoe: the wide, heavy-blade is a low-tech, but efficient way to remove turf.

Ground cover: A plant, such as ivy, liriope, or juniper, used to cover the soil and form a continuous low mass of foliage. Often used as a substitute for turfgrass.

Grass collector: collects grass clippings into a bag rather than dispersing back onto the lawn.

Grass leaf: grass leaves are alternate, distichous (in one plane) or rarely spiral, and parallel-veined. Each leaf is differentiated into a lower sheath which hugs the stem for a distance and a blade with margins usually entire.

Grass root, roots: the part of grass that has no leaves or buds and usually spreads underground, anchoring the plant and absorbing water and nutrients from the soil.

Grass shears: a slow means of clipping grass along the edge of a garden bed, but necessary where prized flowers grow too close to use a mower or string trimmer.

Gypsum: a white or colorless mineral consisting of hydrated calcium sulfate used in fertilizer.

Habitat: the natural conditions and environment in which a plant or animal lives, e.g. forest, desert, or wetlands.

Hardiness: a plant’s ability to survive the winter without protection from the cold.

Hardiness zone: a region where the coldest temperature in an average winter falls within a certain range, such as between 0° and 10°F.

Heat zone: a region determined by the average annual number of days its temperatures climb above 86°F.

Herbicide, herbicides: a chemical used to kill plants. Pre-emergent herbicides are used to kill weed seeds as they sprout and thus to prevent weed growth. Post-emergent herbicides kill plants that are already growing.

High-wheel mower: refers to walk-behind mowers with larger wheels (typically 9- to 12-inch diameter) in the rear. Low wheel mowers have the same size wheels front and rear.

Horsepower (hp): a measure of the power of an engine. Most push mowers have between 4.0 and 6.5 hp. Adequate for small, relatively flat lawns.

Horticulture, horticultural: the science, skill, or occupation of cultivating plants, especially flowers, fruit, and vegetables, in gardens or greenhouses.

Host: a human, animal, plant, or other organism in or on which another organism, especially a parasite, lives.

Humidity: the amount of moisture in the air.

Humus: thoroughly decayed organic matter. Added to lawns, it will increase a soil’s water-holding capacity, improve aeration, and support beneficial microbial life in the soil. Refers to any organic matter that has reached a point of stability, where it will break down no further and remain essentially as is for centuries, if not millennia.

Hybrid, hybrids: a plant produced from a cross between two plants with different genetic constituents. Hybrids from crosses between crop varieties are often stronger and produce better yields than the original stock.

Hydraulic: relating to or operated by a device in which pressure applied to a piston is transmitted by a fluid to a larger piston, so as to give rise to a larger force.

Hydroseed, hydroseeding: a planting process which utilizes a slurry of seed and mulch. The slurry is transported in a tank, either truck- or trailer-mounted and sprayed over prepared ground in a uniform layer.

Hydrostatic transmission: a variable-speed fluid drive transmission that does not require shifting.

Landscape fabric: a synthetic fabric, usually water permeable, spread under paths or mulch to serve as a weed barrier.

Landscape rake: 36-inch aluminum head mounted on an aluminum or wood shaft, used to remove debris from prepared soil and to level the soil prior to planting a new lawn.

Landscaping: the enhancement of the appearance of land, especially around buildings, by altering its contours and planting trees, shrubs, and flowers.

Larva, larvae: the wingless immature worm-shaped form of many insects that develops into a pupa or chrysalis before becoming an adult insect.

Lawn: an area of closely mowed grass, sometimes part of a yard.

Lawn-and-leaf rake: useful for collecting lightweight material, such as clippings and leaves. Those made from bamboo are usually the lightest and easiest to use, however, they only last a few seasons. Steel rakes and the modern plastics are more durable.

Lawn edger: a half-moon-shaped steel cutting head, mounted to a hardwood handle, keeps lawn edges neat. You can use to cleanly separate a lawn from a walkway or other paved surface, such as a concrete sidewalk or asphalt path. Offers a more finished appearance than can be achieved by merely mowing over the border of the lawn and walkway (which frequently permits tufts of low-growing grass to hang over onto the walkway, resulting in an irregular or ragged appearance). You can also use to trim away excess when laying sod along irregular lawn edges.

Lawn restoration: improving a lawn without killing or removing all of the existing turf.

Lawn roller: use this tool to prepare soil for planting. Cost to own is inexpensive, but it does take up storage space.

Leaf compost: compost made of leaves.

Leaf sheath: the leaf sheath and leaf blade are continuous and the sheath wraps around the culm above the node.

Lesion, lesions: an injury or wound.

Lime, limestone: a white or grayish mineral compound used to combat soil acidity and to supply calcium for plant growth.

Loam: a soil consisting of a mixture of sand, silt, and clay is ideal for growing.

Machete: a large heavy knife with a broad blade used as a weapon or as a tool for cutting through vegetation, especially in Central and South America and the Caribbean.

Magnesium: a light silver-white metallic element for use in alloys, metallurgy, photography, fireworks.

Manual aerator: foot-powered and easy-to-use, a manual aerator is fine if you have a small lawn and time on your hands.

Manure: animal excrement, often mixed with straw, used as fertilizer for soil.

Mass planting: filling an area with one or a few kinds of plants, such as ground covers, spaced closely together. Often planted to create a bold, dramatic effect or to reduce lawn maintenance.

Metamorphosis: a complete or marked change of physical form, structure, or substance.

Microclimate: conditions of sun, shade, exposure, wind, drainage, and other factors that affect plant growth at any particular site.

Microbe, microbial: a microscopic organism, especially one that transmits a disease.

Microorganism: a tiny organism such as a virus, protozoan, or bacterium that can only be seen under a microscope.

Micro-topography: variations in the height and roughness of the ground surface. The surface features of a material, or of the earth or other body, on a small or microscopic scale.

Mist: a thin gray cloud of water droplets that condenses in the atmosphere just above the ground.

Mixture, mixtures: two or more species of grass.

Monostand: a single type of seed is planted, not a mixture

Mowing deck: the business end of the cutting machine that houses the blade or blades.

Mowing strip: a row of bricks or paving stones set flush with the soil around the edge of a lawn area and wide enough to support the wheels on one side of a lawn mower.

Mulch, mulches: a layer of bark, peat moss, compost, shredded leaves, hay or straw, lawn clippings, gravel, paper, plastic, or other material spread over the soil around the base of plants. During the growing season, mulch can help retard evaporation; inhibit weeds, and moderate soil temperature. In the winter, a mulch of evergreen boughs, coarse hay, or leaves is used to protect plants from freezing.

Mulching: the process of cutting and re-cutting clippings into fine particles that fall back into the turf, decompose, and restore nutrients and water to the soil.

Mulch kit: a mulching blade and, as needed, a mulch plug.

Mulch plug: an insert that covers a discharge opening, and maintains the circular shape on the underside of the deck when a mower is in mulching mode.

Mycoherbicides: a bioherbicide based on a fungus.

Mycelia, mycelium (fungal): a loose network of the delicate filaments that form the body of a fungus, consisting of the feeding and reproducing of hyphae.

Nitrogen: a nonmetallic element that occurs as a colorless odorless almost inert gas and makes up four fifths of the Earth’s atmosphere by volume, and is used in fertilizers.

Node: a joint in grass plants from which leaves emerge.

Nurse grasses: annual grasses used to protect perennial grasses from excess wind and sun as they establish.

Nutrient, nutrients: nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, and other elements needed by growing plants and supplied by minerals and organic matter in soil and by fertilizers.

Potassium: a soft silvery white highly reactive element of the alkali metal group used in fertilizers.

Potent: producing a powerful effect on the body or mind when taken, eaten, or drunk.

Power aerator: available in several styles, aerators loosen compacted soil by making many small holes in it. The best units have hollow coring devices that lift plugs of soil and turf from the lawn as the unit passes over it. Less-effective units create holes by pushing spikes into the lawn.

Power dethatcher: gas-powered, this tool has heavy, metal tines that whip the lawn as you pass the machine over it. Power rakes are great for removing light thatch and for prepping a lawn for overseeding.

Power edger: gasoline- or electric-powered tool with a short blade that can trim grass horizontally at lawn edges or vertically to create and maintain edges.

Power seeder (slit seeder): similar to a vertical mower, this gasoline-powered unit cuts many shallow grooves in prepared soil or turf and sows grass seed at recommended rates.

Power tiller: available in many styles and capacities, from small soil mixers to large, 8-horse-power units. Tillers are ideal for alleviating compaction in preparation for a new lawn or for mixing in soil amendments, such as lime, fertilizer, and compost. Some tillers are available with power rake and aerating attachments.

Prairie grass: grass native to prairie regions.

Pressure-treated lumber: lumber treated with chemicals that protect it from decay.

Prime: pouring gasoline into a carburetor.

Pruning saws: use for wood branches up to three inches in diameter.

Pruning shears: used to cut branches up to ½ inch in diameter.

PTO (power takeoff): the point(s) of attachment for mower blades and other powered attachments found on riding mower and tractors. PTO controls on late-model zero-turn-radius mowers are electric.

Pupae: an insect such as a moth while it is changing inside a cocoon or hard shell

Pustule: a spot on the skin that is filled with liquid

Pythium blight: a lawn disease also known as grease spot or cottony blight, spreads rapidly and causes die-off.

Radius: distance from the center of a circle to its edge, or a straight line from the center to the edge.

Rain gauge: a piece of equipment used for measuring the amount of rain that falls.

Rain sensor: a device that sends a signal to the automated home sprinkler system’s controller that rain is falling so that the controller will turn off and/or delay the restart of sprinklers.

Recoil starter: requires you to pull a handle attached to a rope to start the engine. With a fresh spark plug, and following directions for priming or choking, most engines will start with one or two pulls.

Retaining wall: a wall built to stabilize a slope and keep soil from sliding or eroding downhill.

Rhizomes: underground runners of some types of plants that extend laterally to create new plants.

Root: the part of a plant that grows under the ground, through which the plant gets water and food

Rosette: a circular or spiral cluster of leaves at the base of the stem of a plant.

Rot: to be reduced, damaged, or broken by the action of bacteria or fungi, or affect something organic in this way.

Rotary spreader: a rotary spreader flings seed or amendments over a wide area, thereby covering ground faster than drop spreaders. However, it is not well suited for use on wind days or with small, irregularly shaped lawns.

Rotary sprinklers: sprinklers, usually driven by gears, designed to cover large areas. They rotate across a preset arc, such as 90 degrees for placement in a corner, and deliver water in a sweeping motion.

Scalp, scalping: accidental damage to the turf caused by the blades coming into direct contact with a high spot. Anti-scalping wheels and rollers fitted on the mowing deck prevent, or at least limit, the chance of this happening by keeping the deck a minimum height above the turf.

Scarify: to make scratches on or superficial incisions in the skin, as a traditional cosmetic practice in some cultures or as a medical procedure

Seed, seeded: a plant part produced by sexual reproduction that contains the embryo and gives rise to a new individual. In flowering plants it is enclosed within the fruit.

Seed head: a plant part produced by sexual reproduction that contains the embryo and gives rise to a new individual. In flowering plants it is enclosed within the fruit

Seedlings: a young developing plant that has been grown from a seed.

Selective pruning: using pruning shears to remove or cut back the branches of woody plants, usually to give the lawn greater sun exposure.

Self-limiting disease: terminates by the natural course of events

Shovels: round-point shovels are for moving large quantities of fine-textured material, such as sand, soil, or non-fibrous mulches, from one place to another. Long-handled shovels should be selected by weight—the lighter the shovel, the easier it is to dig. D-handled shovels are only good for digging in trenches.

Shredded bark: used in mulch.

Side-discharge deflector (chute): used in the side-discharge mode, this safety attachment directs clippings and debris downward and away from the operator.

Sieves: an object that you pour a liquid or mixture through to remove the solid or largest pieces. It consists of a net of very thin wires on a metal or plastic ring.

Sideshoots: as a plant matures, you will see “side shoots” appear, where the main leaf stem joins the stalk.

Sift soil: to pass a substance through a sieve to separate out or break up coarse particles.

Sludge: a solid deposit found at the bottom of a liquid

Snow blower (snow thrower): a machine designed to remove snow.

Socket wrench: a long-handled wrench with interchangeable heads that fit over nuts and bolts of various sizes and a ratchet that makes tightening nuts and bolts easier.

Soil compaction: compaction occurs when a force exerted on soil exceeds its bearing strength. As force increases, soil aggregates re-arrange or are destroyed, resulting in a structure-less soil condition. Because the soil bulk density increases drainage and aeration decreases and the soil can take years to recover.

Soil structure: determined by how individual soil granules clump or bind together and aggregate, and therefore, the arrangement of soil pores between them. Soil structure has a major influence on water and air movement, biological activity, root growth and seedling emergence.

Solarization: bakes grass, weeds, and weed seeds to death under a layer of clear plastic.

Sour soil, acid soil: soil with a pH measure below 7. Most soils in the eastern third of the United States and Canada and along the West Coast are naturally acidic.

Sow: to scatter or plant seed on an area of land in order to grow crops.

Spade: often mistakenly called a shovel, spades have flat or gently curved blades and are for planting or transplanting, edging, and turf removal.

Spark plug: a device that ignites the fuel mixture in the cylinder in an internal-combustion engine by emitting a spark

Species: indicates plants that have additional common attributes and similar methods of reproduction.

Spores: a small, usually one-celled reproductive structure produced by seedless plants, algae, fungi, and some protozoans that is capable of developing into a new individual

Sprayer: used for dispensing insecticidal soap or oil solutions. Sprayers are typically available in canister or backpack styles with 2- to 4-gallon polyethylene tanks and interchangeable nozzles for varying applications patterns and rates.

Spray sprinklers: sprinklers that produce sprays of various widths without rotation. They have shorter spraying radii than rotary heads and are consequently used for small areas, but they can deliver more gallons per minute.

Spreaders: precision is the main difference between the two types of spreaders. A drop spreader distributes seed, fertilizer, and other amendments, such as lime, in swaths the width of the spreader. Settings allow you to control the amount distributed. A rotary spreader flings seed or amendments over a wide area, thereby covering ground faster than drop spreaders. However, it is not well suited for use on wind days or with small, irregularly shaped lawns.

Sprigs: cut-up lengths of rhizomes or stolons that can be broadcast and pressed into the soil to establish new lawns.

Sprinkler system: a method for watering lawn and plantings via underground pipes and sprinklers. A controller, when set to run, directs water to one station (valve) at a time for a specified amount of time. Afterward, it closes the valve and opens the next valve. Each station sends water to one zone, which typically consists of a group of sprinklers.

Stamped deck: using a press to form lighter gauge steel.

Station: a group of sprinkler heads controlled by an automatic valve.

Stem: grass has hollow stems called culms; nodes plug the culms and give rise to leaves.

Stick edger: a half-moon-shaped steel cutting head, mounted to a hardwood handle, keeps lawn edges neat. You can use to cleanly separate a lawn from a walkway or other paved surface, such as a concrete sidewalk or asphalt path. Offers a more finished appearance than can be achieved by merely mowing over the border of the lawn and walkway (which frequently permits tufts of low-growing grass to hang over onto the walkway, resulting in an irregular or ragged appearance). You can also use to trim away excess when laying sod along irregular lawn edges.

Straw mulch: the stalks of threshed cereal crops such as wheat or barley. Use: bedding and food for animals, weaving into objects such as baskets, thatching.

String trimmer: gas-, electric-, or battery-powered models use a plastic line that rotates at a high speed to trim grass or weeds along lawn edges and near fixtures, such as lampposts and fences. The better-balanced and easier-to-use models have the power unit at the top end of a long sharp and an adjustable handle in the middle. Cutting swaths range from 6- to 10-inches for cordless units, 8- to 15-inches for corded electric models, and 15- to 18-inches for gas-powered units.

Tamp: to pack or push something down, especially by tapping it repeatedly.

Taproot: a long tapering root that extends downward below the stem of some plants and has fine lateral roots. It often serves as a food storage organ, e.g. in the carrot.

Temperate: describes a climate that has a range of temperatures within moderate limits

Terraced bed: a flat, fairly narrow, level strip of ground, bounded by a vertical or steep slope and constructed on a hillside so that the land can be cultivated.

Thatching rake: designed to remove thatch from your lawn without damaging the turf. The angle of the rake head adjusts to control the depth of the tine penetration.

Thatch: a mat-like buildup of grass roots and stems (but not of grass blade clippings) that if too thick can inhibit healthy growth. Un-decomposed stems and roots that accumulate near the soil surface.

Throttle: a valve used to control the flow of a fluid, especially the amount of fuel and air entering the cylinders of an internal-combustion engine

Till: to prepare land for the growing of crops by plowing or harrowing.

Tolerance zones: the ability of an organism to survive in extreme conditions

Top-dressing: to spread a thin layer of something on the ground, especially fertilizer on the surface of soil, a growing crop, or a lawn.

Top layer: usually the top two inches of soil.

Topsoil: the upper fertile layer of soil, from which plant roots take nutrients

Torque wrench: a wrench with a gauge attached for regulating the amount of torque applied to a bolt.

Transaxle: a combined front axle and transmission in a motor vehicle with front-wheel drive.

Transitional zone: within this zone, no one type of grass will do well in all weather conditions.

Trichoderma harzianum: a fungus that is also used as a fungicide.

Trowel: a hand tool with a short handle and a curved tapering blade, used for making holes to put plants and seedlings in and for other light digging work.

Tubular flower: longer than wider, shape of a tube.

Tubular frame: a frame made from tubes.

Turf: a dense thick even cover of grass and roots in the top layer of soil.

Turf edger: a half-moon-shaped steel cutting head, mounted to a hardwood handle, keeps lawn edges neat. You can use to cleanly separate a lawn from a walkway or other paved surface, such as a concrete sidewalk or asphalt path. You can also use to trim away excess when laying sod along irregular lawn edges.

Turfgrass: a dense thick even cover of grass and roots in the top layer of soil.

Turf-type: denser, finer-leaved, and have the advantage of being more resistant to diseases and insects.

Turning radius: equals half the diameter of an uncut circle when mowing with the wheels turned the maximum amount.

Twin-cylinder: two cylinder internal combustion engine with the cylinders arranged on opposite sides of the crankshaft.

Variety: a taxonomic category of related organisms, especially plants, of a rank below a species. Varieties of a species generally have distinguishing characteristics such as a flower color and may arise naturally or through deliberate plant breeding.

Vegetative matter: relating to or typical of vegetation, plants, or plant growth.

Vertical mower: resembling a lawn mower, a vertical mower is useful for dethatching and for scarifying the soil in preparation for seeding. This mower has several vertically mounted blades set to penetrate the soil slightly.

Zero-Turn: a machine that steers using the rear wheels and pivots through 180 degrees without leaving a circle of uncut grass (the radius or diameter of the uncut circle is one measure of a conventional mower’s cutting ability).

Zone: an area of lawn or planting within a landscape that requires similar amounts of water throughout.